Study of the relative, free diffusion velocities of electrolytes in aqueous medium

Abstract

A novel liquid diffusion tube closed and cylindrical termed Diffusimeter was fabricated from glass tube and straight bore stopcocks to measure relative velocities of electrolytes in free diffusion. Solutions of two electrolytes known to give characteristic reaction were put one above each of two stopcocks and then released concurrently to diffuse head on through water in the diffusion path and finally to produce a precipitate or color as indicator at the encounter. Experimental objective required entry of time elapsed for the reaction mark to appear and the distances traveled by the electrolytes. The velocity ratio termed distance traveled ratio (DTR) was found to match with the Molar Mass Ratio Square Root (MMRSR) of the electrolyte pair taken in order. A direct proportionality between the velocity and the square root of molar mass was thus revalidated. The heavier electrolyte moved faster contrary to the gaseous diffusion. The results hinted hydration numbers of the diffusing electrolytes. Diffusion velocities of thirty salts were determined using this novel, innovative Diffusimetric Method named DTR model. Surprisingly NH4Cl and NH4SCN showed similar velocities. HCl and LiCl showed low diffusion rates due to their cation’s high charge to size ratio. Apparently MgCl2, CaCl2, and SrCl2 diffused with one H2O each but BaCl2, AgNO3, and FeIII alum with none. NaCl showed relatively high rate which traces its fitness as antibacterial agent and bio-salt in human. Na2SO4 and K2SO4 showed identical velocities which together with metatheses hypothesize sylvite mineral formation mechanism over geological periods. Close diffusion rates of ZnCl2 and CdCl2 traces reasons for cadmium’s presence in zinc ores. Diffusion controlled effects are shown in FeIII salt’s reactions with NH4SCN; the DTR reveals reactant pair’s encounter nature at their conjunction. Manipulating electrolyte’s concentrations crystalline precipitates were obtained.